# On the Exact Variance of Tsallis Entanglement Entropy in a Random Pure State

@article{Wei2018OnTE, title={On the Exact Variance of Tsallis Entanglement Entropy in a Random Pure State}, author={Lu Wei}, journal={Entropy}, year={2018}, volume={21} }

The Tsallis entropy is a useful one-parameter generalization to the standard von Neumann entropy in quantum information theory. In this work, we study the variance of the Tsallis entropy of bipartite quantum systems in a random pure state. The main result is an exact variance formula of the Tsallis entropy that involves finite sums of some terminating hypergeometric functions. In the special cases of quadratic entropy and small subsystem dimensions, the main result is further simplified to…

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